Bending sensor based on intermodal interference properties of two-dimensional waveguide array fiber.

We propose a highly sensitive bending sensor based on the intermodal interference properties of a strongly coupled two-dimentional waveguide array fiber (WAF). The interference resonance peaks formed by the SMF-WAF-SMF Mach-Zehnder interferometer are intrinsically the result of interference between the LP(01)-like supermode and other higher order supermodes, displaying supernormal sensitivity to bending in a wide curvature range. The bending sensitivity of the intermodal MZI is a quadratic function of curvature, and the resonance wavelength shift is up to 100 nm within a curvature range 0-10 m(-1). The fabrication reveals briefness, and temperature response shows little impact on the bend sensing precision. The high bending sensitivity and wide sensing range can make this device a candidate for bending discrimination and measurement in widespread areas.

[1]  H. Bartelt,et al.  High precision fiber waveguide arrays for coherent light propagation , 2007, 2007 European Conference on Lasers and Electro-Optics and the International Quantum Electronics Conference.

[2]  B. Eggleton,et al.  Fluid-Filled Solid-Core Photonic Bandgap Fibers , 2009, Journal of Lightwave Technology.

[3]  N. Peyghambarian,et al.  Phase locking and in-phase supermode selection in monolithic multicore fiber lasers. , 2006, Optics letters.

[4]  H. Choi,et al.  All-fiber Mach-Zehnder type interferometers formed in photonic crystal fiber. , 2007, Optics express.

[5]  Tao Zhu,et al.  Highly sensitive bend sensor based on Mach–Zehnder interferometer using photonic crystal fiber , 2011 .

[6]  Gyeong-il Kweon,et al.  Splicing losses between dissimilar optical waveguides , 1999 .

[7]  A. Szameit,et al.  Diffraction control in periodically curved two-dimensional waveguide arrays. , 2007, Optics express.

[8]  J.M. Tang,et al.  Effectiveness of the Use of 3-dB Bandwidths of Multimode Fibres for Estimating the Transmission Performance of Adaptively Modulated Optical OFDM Signals Over IMDD Links , 2009, Journal of Lightwave Technology.

[9]  B. Lee,et al.  Bending sensitivity of in-series long-period fiber gratings. , 1998, Optics letters.

[10]  Yaron Silberberg,et al.  Discretizing light behaviour in linear and nonlinear waveguide lattices , 2003, Nature.

[11]  Ian Bennion,et al.  Bend sensing by measuring the resonance splitting of long-period fiber gratings , 2001 .

[12]  A. Tünnermann,et al.  Nonlinearity and disorder in fiber arrays. , 2004, Physical review letters.

[13]  Jian Ju,et al.  Directional Bend Sensing With a CO $_{2}$-Laser-Inscribed Long Period Grating in a Photonic Crystal Fiber , 2009, Journal of Lightwave Technology.

[14]  T A Birks,et al.  Bend loss in all-solid bandgap fibres. , 2006, Optics express.

[15]  Tingting Han,et al.  Avoided-crossing-based ultrasensitive photonic crystal fiber refractive index sensor. , 2010, Optics letters.